Electrolytically-formed hollow-metal article and the method of its manufacture



ROBINSON Sept. 7 1926.

AL ARTICLE AND THE AGTURE Filed Feb. 25, 1926 ELECTROLYTICALLY FORMEDHOLLOW MET METHOD OF ITS MANUF 2 Sheets-Sheet 1 AL ARTICLE AND THE Sept.7, 1926.

W. R. ROBINSON ELECTROLYTICALLY FORMED HOLLOW MET METHOD OF ITSMANUFACTURE Filed Feb. 23, 1926 2 Sheets-Sheet 2 Patented Sept.

UNITED STATES TIENT QF. lC

WIBT a. Boer-risen, or", nAL'rIMonE, rianYLAivn, :1

ELECTROLYTICALLY-FOBMED HOLLOW-METAL ARTICLE AND THE METHO OF ITS,

My invention relates to formed hollow metal articles, of theirmanufacture,

MnNUFAo'rURE;

Applicationfiled February 23', 1926. Serial No. 90,189.

electrolytically and. particularly includes the manufacturing of saidarticles by electro-formin them on a fusible core.

invention particularly applies to the formation of such metal articlesas spheres, cylinders, ring-shaped bodies and the like, which arecommonly used as automobile vacuum tanks,carburetors,

tanks,

refrigerating machinery,

forth.

oil burners and so I am aware that it is old to electro-form hollowmetal articles of this type by a fusible core in electrodepositing aforming the shape of the article, layer of plating metal on said coreduring rotation thereof in the bath and evacuating said core. Myinvention particularly relates to a novel method of sealing andsimultaneously strengthening such parts of the articles as will beexposed to the se verest stressesin actual service.

In the manufacture of said articles it'is necessary that an orifice beprovided a the core may be evacuated, whether the holtherein throughwhich low article be of a type adapted to have no projection therefromor whet-herit be of'ia projection therefrom to which type having a afloat rod or other device may be attached,

and' itis to the particular sealing of said orifice which my inventionrelates.

aware that hitherto nipples or plugs have been inserted at a fusiblecore, and have predetermined 1 spot on a been integrally bound to thearticle by the plating layer itself. It

has been necessary, hole in these nipples however, to provide a for theevacuation and the problem of sealing said hole has still existed. 'Inaddition it tically impossible joint of nipple and the required strengthone plating layer.

hasbeen found praccom'mercially to form a between said aware that glassor spun metalfloats have been provided with integral to receive theplug, so far as I am aware, I am the first to provide an electro-formedhollow metal article having a stantially radial lntegral neck.

hollow sub- The advantages of a neck integral with the article are asfollows The plug may-be readily inserted in the neck without the usehollow article is rendered at a point where it norbase of the neckmall-y contacts the which it isused.

of solder. The seamless at the liquid in the apparatus n It provides avery satisand'the method sofar as I am aware I am While I am necksadapted factory .means float away from contact with said liquid. In theprocess ofxits manufacture it facilitates theseparationof the cathodestem from the article. It also provides means whereby a flexible tubemay be'readily attached, to saidarticle to facilitatea positive air teston' said article prior to final assembly. As stated hitherto, wherethenipple has been integrally joined to the metal article a weak jointhas been present, neck provides strength est point of the float. It alsorenderspossible, as will'be apparent, the; substitution of a threadedjoint with its tages I between the plug and article in place whereas anintegral vof the former soldered or electrolytic joints.

here the nipple has'been attached directly to the core, it has tended toseparate therefrom 'duringrotation thereof inthe bath,

attendant advanfor securing'the plug to the athithert'o the weak- 7'which danger is eliminated by providing-an integral neck onsaid'article. r V

A further advantage of my invention 're-' sides in the peculiar typeofelosurefor said neck or orifice-which I employ. J VVhile I am awarethat various types ;of cast, stamped ormachined plugs have "hithertobeen provided,

vide a simpler. screw; plug, which maybe imanufa'cturedin .quantities1at a relatively low cost on aniautomat icxscre'w machine. I preferably.provide said plug with means whereby it may be screwed within saidorifice. In preferred embodiment said means comprises 'an ann'nularflange on the outer end thereof;-' AsI form the .outer-periphery of thethreaded portion of said screw plug of approximatelyv the/diameter ofthe inner periphery of said neck or orifice it is obvious that as saidneck is held in position by a clamp or in the screw'plug is-threadedtherein-acooperating thread will be cut on theinnerjperiphcry of theneck to assist, inbinding and retaining said plug'to saidneck.

7 an automatic machine, as

. V To form an hermetic seal over said plug there is no, scrap loss oftion: asmay'hereinafter appear will behest understood from a descriptionof the accompanying drawings, which illustrate various embodiments of myinvention.

Inthe drawings z- Fig. 1 is a diagrammatic view of a section of anelectro-plating tank showing how the plating metal? iselectrodepbsitedto form the hollow metal articles in my process, while the core" isrotated in the electroplate ing' bath Fig. 2 i's a cross isectional viewofthe fusibl'e core of my invention, having: a cathode stemattachedithereto, after it has been withdrawn from the plating-' bathwiththe holl'ow m'etal shell ofzthe article plated thereon;

F ig. 3 is'a' cross sectiona'l view of the hol- 10w metal article afterthe core has been evacuated therefrom in the act of having theplugthreaded into the neck thereof Fig- 4, is a plan view of the step 1nthe recess ill-ustratedin Figure 3'sliow1ng the rand clamp I preferablyemploy while threading said plug into said neck; I

Fig. 5 is a cross-sectional viewof the plug 1 preferably employ F i'g. 6is a* perspective view of said plug;

Fig r' is a cross-sectional view of the metal 'articlewith' pluginserted, showing the inserted plug" in elevation;

Fig. 8 is a cross sec'tional view of the article with the cathode stemonce more at tache'df after the" reenforcinglayer of plating meta-l hasbeen depositedaround' the portion of the article adjacent to the neck;

Fig; '91 is a side elevation of a completed float witha connectingrodattached;

Fig. 'l di's a cr ossgsecti'onalview illustratin'g in detail the upperportion of the completed float adjacent tothe neck;

Fig. 11 is a perspective view of a modified form of plug I F ig' 12 is"a cross 'sectional view of a typi" cal cylindrical float such as is usedin the vacuum tank of an automobile.

In the drawings; wherein like characters of reference indicate likeparts throughout, 20" generally indicates a' finished electroforn'ie'd'hollow metal article constructed in accordance with my invention.Although I haveflsh'own asphe'ri'cal float adapted parfor use in tanksas my preferret embodiment, it is obvious that any desired shape ofhollow nretal article may beproduced by my processysuclr as a spheroid,tauru's, etc, for use as hitherto explained. I will first describe the"improved method I employ for" constructing my new electroformed hollowmetal article, and" I will then refer in detail" to the variousnovelfeatures of this structure: I- first for'nr in any well known mannerpreferably by means of 'a mold, a fusible having the configuration ofdea2, sired hollow article. I preferably form said .the rope belt 52 tre-unit i-ncluding the core 22, with a substantially radial neck 24. Sofar as I am aware, I im the first.

to provide an electro-formed hollow metal article with an integralsimultaneously formed neck projecting substantially radially therefrom.I then insert the cathode stem 26, within said fusible core as shown in:Figure 2,; said cathode stem 26 being provided with a lower irregularportion 26, .vhereby it may be securely retained within the core 22,during the plating operation. The cathode stem-26 also is provided witha thread 30 on the upper end thereof for securing it to'the cathodesleeve 42 and pulley 320th the electroeplating bath. After the core 22has beenfor med as explained and the catho'destem 26 secured in placetherein, the unit ismounted by means of the cathode stenr 26 in any ofthe wellknown graphiting or conductor coating. devices which renders thesurface of the fusible core electrically conductive. V V

Figure 1 illustrates a suitable electro plating bath. for use in themethod of my invention which comprises at'ank 34' having anelectroplating solution 86' of desired strength contained therein and asuitable anode 38 suspended therein. To secure a uniform layer ofplating metal on' said core 1: preferably provide means to cause arotatioir of sai-d core 22 in the bath. in my preferred embodiment saidmeans include the pulleys32suitably mounted above said ba ilr so as torevolve horizontally. Said pulleys 82 are provided with-integral sleeves4.0 for detachable securelnent to the vertical: cathode V sleeves 42 bymeans of the wing nuts 44. The cathode sleeves are electricallyconnected with the cathode bar 46' and are provided at their ends withthe interior threads 48.- The outer peripheries of said pulleys 32 areprovided with circrun ferential grooves'eO adapted to receive 54 torevolve saidpulleys and connected cores 22 within said bat-h 36. Thecathode stem 26 is 4.8 ou thelower end of the cathode sleeve 42 as shownthe left hand portion of Figure 1 so that the core 22 may be ent' l-yimmersedwithin'th'e bath 36 and connually revolved therein until asufficient amount of plating metal'56 has been electrodeposited thereon.It is thus obviousthat the metal article 56' is at this point. in theprocess electro -formed on the fusible core Thecore 22 is left in theplating bath 36 until the metal shell 56h'as attainedthe requiredthickness which can be readily calculated from the condition of current,5 temperature, etc.

As soon as. the layer 56 has reached the desired thickness the en- Icathode stem 26, core 22 and electrodeposited hollow article 56 areremoved from the bath by means of driven by the central shaft connectedto" the thread from threaded conunscrewing the stem 26 the cathodesleeve nection 30 and L8 with 4-2. The stem 26 is now shell 56 and thecore' 22 removed by means of first sawing, filing or otherwise cuttingan annular groove 58, as shown by means of a suitable'cutting tool 60,(Fig. 2) in said article 56 near the top of the neck 57 which isapparent, is formed on said core neck 24 integrally with said article 56and the stem 26 is then pulled out of the core 22.

The fusible core 22 is then evacuated from within said article 56through the neck 57 in any suitable manner, either by dissolving it outwith a suitable solvent or by melting it. I then'take a suitable plug 62preferably of a type shown in Figures 56 or llwhich may be readilyturned out in large quantities on an automatic screw machine. Thepreferred embodiment of saidplug 62 shown in Figures 5 and 6has thescrew thread 64 on the outer lower periphery thereof, the annularradially projecting flange 66 on the upper end thereof, and thepreferably annular fillet 68, between said flange 66 and thread 6 L.Said plug 62 is also provided with means to receive the connecting rodtherein, which 3 in my preferred embodiment comprises the extendingpartway threaded axial socket 70 down said plug leaving the solidportion 72 at the base of said plug to effectually seal said hollowarticle. It is essential that said P plug 62 be provided with some typeof means whereby it may be threaded into said neck 57.. Although in thepreferred embodi- 5 and 6 said means ment shown in Figures comprises theannular'flange 66, it may comthe screw slot 74: shown in the upper endof the embodiment of plug shown in Figure 11. 7

The exterior of the threaded plug may then,fif desired be covered withany suitable ed plug 62 into'the neck 57 'of fsaid article' 56 whileholdingthe neck 57 in any suitable manner to cut the cooperating threadon 78 of said neck-f 57 periphery of said neck type of high temperaturecement 76. V

As' stated the outer periphery of the threaded portion of said plug isof approximately the diameter of the inner periphery 78- of said neck 57I then insert the threadthe inner periphery While this may be donein anysuitable manclam 82 com rism I) firmly press the clamp 82 aroundtheouter 57 for said thread cutting operation; When said cement 7 6 2 setsit is obvious that said plug 62 will be secured within saidneck 57 notonly by said" 8 l are drawn to-' a closure 62 applied outer periphery 7I the "-inner periphery '78" of said, neck 1 by cooperating threads 6tand 80'but also by said cement 76." detached. from the I 1 Tore'enfor'ce the portion of the metal article 56 around the neck and theline of jointure of the type of plug used with said preferably employed.lhe cathode sleeves Y 42 may be provided atone end thereof with thesemicircular springs 9 ladapted to clip the object 56 therein. After theneck 57 and shoulder of said hollow article 56 are thoroughly cleaned bypickling,

scratchbrushing,sandblastingor in any other sui'table manner, thearticle 56 is reintroduced in 7 an inverted position in the platingbath36 as shown at the righthand'side of Figure-1 andthe spring clips 94are: clamped around the end of said article opposite from said portion90 and neck 57 and the cathode sleeve i2 is so adjusted that the portion9O of the article 56 adjacent to the neck 57 only willbe immersed insaid bath 36. If desired, a non-conducting threaded plug 96 may beinserted within the socket 70 to prevent internal plating on the threadsthereof.

Since this interior plating takes place ex tremely slowly this' plug96". may be disensed within most cases. ,The article thenleft in thebath 36 and revolved as hithlayer 92 of the desired depth is laidth'ereon, the layerto explained until a reenforcing .er 92 being thusformed integral with the article- 56 itself.- Inadditionto reenforcingthe article, the layer 92 effectually and hermetic'ally seals the plug62 within said neck 7. As shown in Figure 10 a portion 98 of saidlayer'92 may proj let '68V to assist in binding said plug 62 to said article56. As said article 56 is rotated,

itj agitates the bath'86-to acertain extent so that there is a gradualthinning ortaper-ing effectto'th'e out'erlayer 92 which renders the '9).,The ar ticle 56 may then be removed from the plathollow metalarticle'comprising an electroins set within said filline of join-cure ofsaid layer=to saidjarticle 56 qscarely noticeable. 1 (Fig.

ing bath 36 and after rinsing in water or i formed hollow body 56 havinga hollow electro-formed integral neck 57 extending substantiallyradially outwardly in "the outer end of therefrom, upon and secured withment 76, COHlPTlSlIlg the screw plug 62, thefl thereof beingthreadedinto the cooperating threads 64 and 80,- having an annular flange 66outside of saidneck and an annular fillet/'68 between said flange 66 andthread G l, and the axial socket 70 to receive a connecting rod 100extending partway down said plug to the solid portion 72 thereof and areen'forcing layer 92 of an electrolytic metal around the portion 90 ofsaid article adjacent to said neck 57 and over said closure 62 extendingwithin said fillet 68 whereby said closure62 may be secured to saidarticle 56 by said cooperating; threads 16% and 80, said cement 76 andsaid reen-forcing plating layer 92.

WV'hile I have shown in my preferred embodiment a spherical floatspecifically adapted for use in tanks, and provided wit-ha socket TO toreceive the float connecting rod 100 therein, .it is obvious that myinvention may be constructed in any shape such as an. oblate spheroid,cylinder, taurus, etc., without departing from the spirit of myinvention. It is also obvious that a float or hollow object, having aflush periphery may be constructed in accordance with myinvention-having a neck 57 thereof projecting radially inwardly thereofinstead of outwardly, and having the outer surface. of the plug- 62substantially flush with the outer p riphery of said article. I

I have illustrated ,in Fi 'ure 12 a t aical cylindrical float 102 foruse in the vacuum.

tank of an automobile. Said float is preferably constructed with theaxial rod 104 provided with the plugs 106 and 108 secured; by myvthereto and within said cylinderlOfZ method as hitherto described. I

It is obvious that I have not only provided an improved method formaking seamless hollow articles of this description but that I have alsoprovided an improved article with the advanta 'es hereinbefore referredto;

It is understood that my inventionis not.

limited to the specific embodiments shown or methods described and thatvarious deviations may be made therefrom without -de' parting from thespirit and scope of appended claims.

hat I claim as new? and desire to secure by Letters Patent-is:- I r i l.The herein described lmproved method of manufacturing an electro-formedhollow met-al'article, which comprises, forming a fusible core in theshape. of the article hava substantially radial neck, electrodepotitinga layer of plating metal on said core during rotation thereof in thebath to form theh-ollow article provided with a hollowsubstantiallyradial neck on said core, evacuating said core through said hollow neck,

covering the exterior ofa threaded portion ofa plug of approximately'thediameter of the interior of the neck with cement, insertmg the threadedplug into the neck wlnlev holding the neck lirmlyuto-cut a thread ontained within said fusible core in the fusible core in the shape of thearticle hav mg a substantially radial neck, electrode pos ting a layerof plating metal on said core during rotation thereof in the bath .to

form the hollow article provided with .a hol- 1 low substantially radialneck on said core, evacuating said core through said hollow neck,covering the exterior of the threaded portion of a plug of approximatelythe. diameter of the interior of the. n ck with cement, inserting thethreaded plug into the neck, and again electrodepositing a layerv ofplating metal on the portion oftheartiole around the neck to reenforcethe portion of the article adjacent to the neckwherebysaid plug may beretained within said neck by said cement, threads and filial platinglayer.

3. The herein describedimprovedmethod or in-" ifacturing anelectro-formedhollow metal article, which comprises, forming a tusiblecore in the shape of the article has:

ing a substantially radial neck, electrode- 'p-ositin, r a layer ofplating metal on said core during; rotation thereof in the bath to formthe hollow article provided with a hollow substantiallyradial neck onsaid core, evacuating; said core'through said hollow neck, inserting athreaded plug into theneck while holding theneck firmly to cut a threadon the interior of the neck and again electrodepositing a layer ofplating metal on the portion of the article around the neck to reenforcethe portion of the article adjacent to theneck whereby said plug may beretained within said neck by said threads and final plating layer.

l. The herein described improved method of manutacturincanelectro-formed hollow mctal articl-e, which comprises, forming aint: asubstantially radial neck, electrodepositing a layer of plating; metalon said core during rotation-thereof in the bath to form the hollowarticle provided with a hol low substantially radial nechon. said core,evacuating said core through said hollow neck ,and again electrodeposting' alay-er of plating-metal on the portion .of the article around theneck to reeniorce the portion of the article adjacentto the neck.

5. The herein described improved method of manufacturing ancloctro-formed hollow metal article, which comprises, forming a fusiblecore in the shape ofthe article hav ing a substantially radial neck,electrode shape of the article havpositing a layer of plating metal onsaid core during rotation form the hollow article provided with a hollowsubstantially radial neck on said core, evacuating said core through,said hollow neck, securing a plug within said neck, and againelectrodepositing a layer of plating metal on the portion of the articlearound the neck to reenforce the portion of the article adjacent to theneck whereby said plug maybe retained within said neck by, said finalplating layer.

6. Thevherein described improved method of manufacturing anelectro-formed hollow metal article, which comprises, forming a fusiblecore in the shape of the article having a substantially radial neck,electrodepositing a layer of plating metal on said core during rotationthereof in the bath to form the hollow article provided with a hollowsubstantially radial neck on said core, evacuating said core throughsaid hollow neck, covering theexterior of the threaded portion of a plugof approximately the diameter of the interior of the neck with cement,and inserting the threaded plug into the neck while holding the neckfirmly to cut a thread on the interior of the neck.

7. The herein described improved method of manufacturing anelectro-formed hollow metal article, which comprises, forming a fusiblecore in the shape of the article having a substantially radial neck,electrodepositing a layer of plating metal on said core during rotationthereof in the bath to form the hollow article provided with a hollowsubstantially radial neck on said core, evacuating said core throughsaid hollow neck, and securing a plug within said neck.

8. An electro-formed seamless hermetically sealed'hollow metal articlecomprising an electro-formed hollow body having a hollow electro-formedintegral neck extending substantially radially outwards therefrom, aclosure applied within the outer end of said neck by cement, comprisinga screw plug, the outer pe riphery thereof being threaded into the innerperiphery of said neck, having an annular flange outside of said neck,fillet between said flange and thread, and an axial socket to receivethe float rod extending partway down said plug and a reenforcing layerof electrodeposited metal thereof in the bath to a said neck, an annularlytic metal around I thereof being upon and secured an annularing'substantially radially outwards therefrom, a closure applied uponand secured within the outer'end of said neck comprising a plug havingan annular flange outside of fillet below saidv flange and a reenforcinglayer of electro-, the portion of said article adjacent to saidneck andover said closure extending within said fillet whereby said closure maybe secured to said article by said reenforcing plating layer.

10; An electro-formed seamless hermetically sealed hollow metal articlecomprising an electro-formed hollow body having a.

hollow integral electro-formed neck extending substantially radiallytherefrom and a closure applied upon and secured within the" outer endof said neck comprising a plug and a reenforcing layer ofe'lectrolyticmetal around the portion of said-article adjacent said neckand over said closure whereby said closure may be secured to saidarticle by said reenforcing plating layer.

11. An electro-formed seamless hermeti- I cally sealed hollow metalarticlecomprising an electro-formed hollow body having a hollowelectro-formed integral neck extending substantially radially outwardstherefrom anda closure applied upon andsecured within the outer end ofsaid neck by cement com prising a screw plug, the outer peripherythreaded into the inner, pe riphery of said neck, said plug having meansthereon whereby it may be threaded into said neck, and an axial socketto receive a connecting rod extending partway down said plug and areenforcing layer of electrolytic metal around the portion of saidarticle adjacent to said neck and over said closure. whereby saidclosure may be secured to said article by said thread cement andreenforc -WIRT n. ROBINSON.

